Add backslashes

Author: ValerianRey

.github/workflows/tests.yml

@@ -44,10 +44,10 @@ jobs:
         run: pdm install --group test --frozen-lockfile
       - name: Run unit and doc tests with coverage report
         run: |
-          pdm run pytest tests/unit tests/doc
-          --ignore tests/unit/aggregation/test_cagrad.py
-          --ignore tests/unit/aggregation/test_nash_mtl.py
-          --ignore tests/doc/test_aggregation.py
+          pdm run pytest tests/unit tests/doc \
+          --ignore tests/unit/aggregation/test_cagrad.py \
+          --ignore tests/unit/aggregation/test_nash_mtl.py \
+          --ignore tests/doc/test_aggregation.py \
           --cov=src --cov-report=xml
       - name: Upload results to Codecov
         uses: codecov/codecov-action@v4